Networks for connecting together a number of computers and associated electronic devices are now common place in a wide variety of environments. A network can be as small as a local area network consisting of a few computers and/or other electronic devices, or it can consist of many devices and computers distributed over a vast area. Virtually any electronic device equipped with the necessary hardware can be connected to a computer via a network. Suitable electronic devices include lamps, television sets, VCRs, video cameras, telephones, amplifiers, CD players, equalizers, etc.
Each computer and/or electronic device that is connected to the network and is capable of communicating with other electronic devices or computers connected to the network can be referred to as a node. An underlying network protocol is used to establish communication and ensure reliable transfer of information between the nodes of the network. A network can involve permanent connections, such as cables, or temporary connections made through telephone or other communications links. Communication between nodes can break down because of a malfunctioning or nonfunctioning node or because of a severed cable, wire or other communications link between two nodes on the network. Unfortunately, when a break in communications via the network occurs, there is no satisfactory system for immediately determining and indicating that a network break has occurred.
Accordingly, a method and apparatus for instantly determining and indicating the existence of a break is needed. The method and apparatus should provide any users of the network with an immediately recognizable signal of which nodes continue to communicate with one another. Further, the method and apparatus should neither depend on the type of underlying network protocol, nor interfere with the normal operation of the network. As described in the following, the present invention provides a simple and elegant method and apparatus that meet these criteria.